Method of and means for compacting fibrous web material



Nov. 3, 1959 R. M. ROCHESTER METHOD OF AND MEANS FOR COMPACTING FIBROUS WEB MATERIAL Filed April 26, 1955 llb PoYM POCA'EST'Q,

' INVENTOR- ATTORNEYS.

United States Patent METHOD OF AND MEANS FOR COMPACTING FIBROUS WEB MATERIAL Roy M. Rochester, Abbeville, S.C., assignor to Deering Milliken Research Corporation, Oconee County, S.C., a corporation of Delaware Application April 26, 1955, Serial No, 504,013

11 Claims. (21. 19-66) This invention relates to the processing of textile fibers in which the fibers are formed into a relatively thick pad or lap and are wound into a so-called lap roll on a picker machine.

As is well known in the art, a picker machine includes a feed apron on which loose textile fibers are placed and which feed apron delivers a reasonably even amount of the fibers to a beater which parallelizes the fibers and delivers the fibers to and between a pair of condensing screens which, in turn, deliver the fibers through compress rolls or calender rolls in the form of a lap; that is, in the form of a compacted mass of fibers approximately one inch thick, and thereafter the lap is rolled onto an arbor to form a lap roll.

Now, although the calender rolls or compress rolls have compressed the lap during its formation to a certain extent, the lap tends to expand or swell, as it leaves the nip of. adjacent calender rolls, to a considerable extent thereby limiting the diameter of the lap roll that could be produced on a machine. Prior to the advent of conveyor equipment in textile plants, a picker lap roll weighing in excess of sixty pounds could not be conveniently handled by one person. However, with the installation of conveyor equipment, a considerably heavier picker lap roll can be handled with ease.

It is therefore an object of this invention to provide an improved method of and apparatus for compressing or compacting a fibrous web material which includes heating the web, to a temperature far exceeding normal room temperature, prior to and/or during movement of the web through the calender rolls so the calender rolls not only compress the fibrous lap but also heat'set the fibrous lap to a minor extent in a manner similar to that in which a heated flat-iron will press the wrinkles out of a piece of cloth. Thus, as the picker lap leaves the calender rolls, it does not tend to expand or swell to anywhere near the extent that it has when the fibrous material has not been heated, thereby forming a much denser or more compact picker lap roll than has heretofore been possible and also materially lessening the tendency for the lap to split when it is subsequently fed to a carding machine or in other subsequent processes.

Of course, since the improved method and apparatus provides means for maintaining the density of the lap as it from the calender rolls, it is apparent that the capacity of a particular picker machine is substantially increased to the extent that much larger lap rolls may be formed on a particular machine than has heretofore been 'ossiblc.

in carrying out the improved process it has been found that the heat may be applied directly to the fibrous web or to and through the fibrous web to the calender rolls, or the calender rolls may be heated internally or externally to the desired optimum temperature.

It is another object of this invention to provide an improved method of compacting a fibrous lap material which includes applying sutficient moisture to the fibers to cause the fibers to coalesce when subsequently sub- 2,910,732 Patented Nov. ,3, 1959 jected to heat and pressure and thereafter, applying heat to the fibers in web form while passing the fibers through calender rolls.

Some of the objects of the invention having been stated, other objects will appear as the description pro ceeds when taken in connection with. the accompanying drawings, in which- Figure 1 is a somewhat schematic perspective view of the discharge end of a picker machine showing electrically heated calender rolls and showing a lap roll as it wound subsequent to the calender rolls or compress to s;

Figure 2 is an enlarged somewhat schematic vertical sectional view, mostly in elevation, taken substantially along line 2-2 in Figure 1 and showing one form of means for applying heat to the lap as embodied in internally electrically heated calender rolls;

Figure 3 is an enlarged view of one end of one of the rolls shown in Figure 2 and its corresponding bearing housing;

Figure 4 is a schematic isometric view showing a group of calender rolls in association with a second form of means for applying heat to the lap as embodied in a heater positioned exteriorly of the calender rolls;

Figure 5 is a schematic vertical sectional view taken substantially along line 5-5 in Figure 4 further illustrating how heat is applied to the lap by means of electrically operated heaters disposed exteriorly of the calender rolls and also showing how moisture may be applied to the lap;

Figure 6 is a view similar to Figure 2 showing a third form of means for heating the lap as it passes between adjacent calender rolls as embodied in internally heated calender rolls which are heated by steam or hot water.

Referring more specifically to the drawings, the discharge end of a picker machine is shown in Figure l which includes opposed side frame members 10 and 11 whichsupport a housing 12 in which conventional rotatable condensing screcns, not shown, are disposed and which screens feed a relatively thick web of textile fibers W, commonly known as a lap, to a plurality of vertically arranged compress rolls or calender rolls, there being four such calender rolls shown in Figures 1 and 2 indicated at 21, 22, 23, M. The calender rolls are driven in a conventional manner, well known. in the art.

The lap W passes from the condensing screens disposed within the housing 12 and between the first and second calender rolls 21, 22, then half-way around the calender roll 22, then between the calender rolls 22, 23 and then substantially half-way around the calender roll 23 and then passes between the calender rolls 23, $24 from whence it passes onto conventional driven take-up rolls 25, only one of which is shown in Figure 1. The take-up rolls 25 wind the lap W around the lap pin or arbor, not shown, to form a lap roll L. The structure as generally described heretofore is well known in the art and a detailed description and illustration thereof is deemed unnecessary.

Howeventhe improved process includes the application of heat substantially above room temperature to the lap W and, in the first form of the invention shown in Figures 1, 2 and 3, the heat is applied to the lap W by electrically heating the calender rolls 21, 22, 23, 24 internally. Accordingly, a novel means is provided for journaling the heated calender rolls in order to accommodate a heating element within each of the calender rolls or, at least, within one of the calender rolls as shown in Figure 2.

All of the calender rolls Ill, 22, Slit, 24, may be identical and, accordingly, only the calender roll 22 will be described in detail. The calender roll 22 is of hollow construction and is provided with reduced journal por tions 26, 27 on opposite ends thereof. The journal portions 26, 27 are suitably journaled, preferably by sealed anti-friction bearings 30, 31, in respective vertically movable bearing blocks or housings 32, 33 suitably guided for vertical movement in the frame members 10, 11. The journal portion 26 of the calender roll 22 is tubular; that is, it is provided with an axial passageway 35 which communicates with the interior of the hollow calender roll 22 and through which a pair of wires or conductors 36, 37 extend.

The inner ends of the conductors 36, 37 are connected to opposite ends of an electrical heating unit or heating element 40, preferably in the form of a so-called Calrod resistance unit. It will be noted in Figures 2 and 3 that the bearing housing 32 extends outwardly from the frame member beyond the outer end of the tubular journal portion 26 of calender roll 22 and has an insulation sleeve 39 fixed thereon which is encircled by a pair of spaced metallic slip-rings 41, 42 to which the outer end of the conductors 36, 37 are connected. The outer end of the bearing housing 32 may be closed by a closure plate 43.

The outer wall of the housing 32 supports a pair of brushes 44, 45 suitably insulated from the housing 32. The brushes 44, 45 bear against the respective slip-rings 41, 42 and have respective conductors 46, 47 leading therefrom to a suitable thermostatic switch shown schematically and indicated at 48 in Figure l. The thermo static switch 48 controls the flow of current from a suitable source, not shown, to which wires or conductors 49 are connected, to each of the calender rolls 21 to 24, inclusive. The thermostatic switch 48 maintains the calender rolls at a constant temperature of one hundred fifty to two hundred fifty degrees Fahrenheit, depending upon the nature of the fibers and the speed at which they are processed through the calender rolls.

It is thus seen that the calender rolls 21 to 24, inclusive, heat the lap W as it passes therethrough so the fibers in the lap W tend to remain compacted to a degree which has not been attainable heretofore when the lap has not been heated during compressing of the fibers thereby minimizing expansion of the web as it leaves the nip of the two bottom rolls 23, 24 and thus resulting in a tightly compacted lap roll L so that a substantially greater length of the lap W may be included in the finished roll L than has heretofore been attainable on particular machines.

The method as thus far described is particularly satisfactory in the processing of synthetic staple fibers such as cellulose acetate, viscose, Dacron, Orlon and the like. However, in the processing of natural fibers, such as cotton fibers, it is desirable, in order to avoid flufiing of the cotton or other natural fibers during and subsequent to the compressing operation, to apply a relatively small percentage of moisture to the fibers at some time in advance of passage of the fibrous lap W through the nip of the two top rolls 21, 22. The fibers may be moistened, but not saturated, while in a loose or free condition, such as when they are deposited on the feed apron of the picker, or after the loose non-compressed lap is formed, subsequent to the screens in housing 12, if desired.

To this end, a moisture applying means is shown in Figure 1 which is embodied in a suitably perforated pipe or conduit 50 which is preferably closed at one end thereof and to the other end of which a pipe or conduit 51 is connected for feeding liquid, preferably under pressure, from a suitable source S into the pipe 50, the perforations in the pipe 50 serving to direct a fine spray of moisture onto the lap W in advance of the lap passing between the nip of the upper calender rolls 21, 22. The pipe 50 may be suitably supported by the housing 12. The moisture applied to the fibers in the lap W, such as by means of the spray pipe 50, may be in the form of any suitable liquid such as water, sizing solution or chemical compositions of a character preferably having electrically anti-static qualities.

It is preferable that the web material or lap W is heated to a temperature of approximately two hundred degrees Fahrenheit when processing a web which is approximately forty inches wide at a speed of approximately six hundred pounds per hour. Of course, the temperature of the lap W may be increased or decreased to a considerable extent just so long as the heat of the lap W is sufficient to render the fibers responsive to the pressure applied thereto. However, the heat applied to the web should not be such that it will scorch the fibers.

Since synthetic staple fibers are made from a plastic material which will set when subjected to excessive temperatures, the heat applied to such fibers should not be sufficient to cause a solid setting of the fibers but only sutlicient to cause them to tend to remain compacted to where they can readily be separated during subsequent carding and other processes. Of course, it may not be necessary to apply moisture to synthetic fibers but, since the heat removes from twenty-five percent to thirty percent of the moisture normally present in the fibers, it is desirable that moisture be applied to natural fibers prior to their passage between the nip of the upper calender rolls.

In the second form of the invention shown in Figures 4 and 5, the calender rolls are indicated at 21a, 22a, 23a, 24a and these calender rolls may be conventional in all respects and may be mounted in a conventional manner, since the web or lap, indicated at Wa in Figures 4 and 5, is heated by means exteriorly of the calender rolls. The means for applying moisture to the fibers in the lap Wa is shown schematically in Figure 5 and indicated at 50a. The moisture applying means 50a may be identical to the moisture applying means 50 in Figure 1.

It will be observed in Figures 4 and 5 that a plurality of heat radiating units are provided which are preferably in the form of infrared heaters 55, 56, 57 mounted in respective reflector shields 60, 61, 62. The infrared heating units may be located in any convenient position adjacent the path of travel of the lap Wa as it passes through the calender rolls and a greater or lesser number of infrared heating units may be used, if desired. In fact, a single radiant heating unit may produce the desired results. The heating units are preferably arranged as shown in Figures 4 and 5 wherein it will be observed that the first heating unit 55 is disposed closely adjacent and above the path of travel of the lap Wa at a point closely in advance of the nip of the two uppermost calender rolls 21a, 22a. The second heating unit 56 is disposed closely adjacent that portion of the periphery of the second calender roll 22a which is engaged by the lap Wa so the infrared heating unit 56 not only heats the web or lap Wa, but it also heats the exterior of the second calender roll 22a.

The infrared heating unit 57 is also positioned adjacent the third calender roll 23a for heating the lap Wa in the same manner in which it is heated by the infrared heating unit 56 as it passes in engagement with the second calender roll 22a. The infrared heating system shown in Figures 4 and 5, including one or more infrared heating units, may be used in combination with the internally electrically heated calender rolls such as that shown in Figure 2, if desired. However, in this instance, the heating element 40 should be only of sufficient size to heat the calender roll without necessarily heating the lap W.

In Figure 6, a third form of the invention is shown including a set of calender rolls 21b to 24b, inclusive, which correspond to the respective calender rolls 21 to 24, inclusive, in Figures 1 and 2. The showing in Figure 6 is provided to illustrate how the interior of the hollow calender rolls may be heated by steam or hot water. All of the calender rolls 21b to 24b, inclusive, may be identical and, therefore, only the calender roll 21b will be described in detail. it will be noted that opposite ends of the calender roll 21b are provided with reduced journal portions 64, 65 which are journaled in respective bearing blocks 66, 67, as by sealed anti-friction bearings 70, 71. The bearing blocks 66, 67 are guided for vertical movement in respective side frame members b, llh corresponding to the side frame members 10, 11 in Figure l. 1

The journal portion 64 of the calender roll 21b is of tubular construction, forming a passageway 73 therein which communicates with the hollow interior of the calender roll 21b and through which passageway 73 a condensate withdrawing tube 74 extends. The inner lower end of the tube 74 is directed to the bottom of the corresponding hollow calender roll 21b and the other end of the tube 74 is communicativcly connected with a suction conduit 75 by means of a suitable rotary pipe fitting 76 of conventional or other construction.

The rotary fitting 76 may be of a type such as is disclosed in U.S. Patent No. 2,673,748 issued to Harmon L. Shaw on March 30, 1954. Accordingly, a detailed illustration and description thereof is deemed unnecessary. The rotary fitting 76 is communicatively connected to the outer end of the tubular reduced journal portion 64 of the calender roll 21!) and establishes communication between the passageway 73 and a steam inlet conduit or hot water inlet conduit 77 communicatively connected to the outer end of the rotary fitting 76.

Each conduit 77 may be connected to a suitable source of'steam or hot water, not shown. It is thus seen that the conduit 77 directs the steam or hot water from a suitable source, not shown, into the corresponding hollow calender rolls and the condensate or water is withdrawn from the calender roll through the corresponding tube 74, the suction conduit 75 being connected to a suitable suction means, not shown.

The use of steam or hot water to heat the calender rolls or roll has the advantage over the other forms of means for heating the rolls internally in that it is impossible to overheat the calender rolls although the picker machine may be stopped for considerable periods, since the temperature of the rolls depends entirely upon the pressure of the steam therein. It is also more economical than the electrically operable heating means disclosed in either Figures 1 and 2 or Figures 4 and 5, since it is more simply constructed. Of course, the electrically operated heating means disclosed in Figures 1 and 2 and in Figures 4 and 5 has the predominant advantage over the use of steam or hot water for heating the calender rolls in that many manufacturing plants are not equipped with a steam source and in some of those manufacturing plants which are equipped with a steam source, it is the usual practice not to operate the steam boiler when it is not required to heat the manufacturing plant, that is, during late spring, summer and early fall seasons of each year. Of course, the thermostatic control 48 shown in Figure 1 will assist, to an appreciable extent, in the controlling of the temperature of the electrically internally heated calender rolls.

The infrared heating system, such as is disclosed in Figures 4 and 5, has an advantage over the internally heated rolls as disclosed in Figures 2 and 5 in that the heat is almost instantly applied to the web material or lap W when the infrared heating units are initially electrically energized so the infrared heating units may be deenergized at any time that the picker machine is stopped and may be again energized at the moment the machine is again paced in operation without the danger of overheating the lap or of running a portion of the lap through the calender rolls without it being adequately heated.

it is thus seen that I have provided an improved method of compressing or compacting a lap of textile fibers including the steps of applying moisture to the lap or to the fibers at some time in advance of a set of calender rolls and thereafter passing the lap through the calender rolls while heating the lap to thereby insure that the lap remains compacted as it is discharged from the calender rolls and wound into a lap roll. Since the lap is more tightly compacted than has heretofore been possible as it is wound into a lap roll, it is apparent that the maximum size of the lap roll which may be formed on any particular picker machine is substantially greater than has heretofore been possible.

In order to assist in distributing the heat radiated by the internal electrical heating unit 40, the wires 36, 37 should be suitably waterproofed and the hollow calender rolls 21-24 should be filled with a heat conducting fluid such as mineral oil, silicone oil or the like.

The arrangement shown in Figure 6 is better adapted for use with steam than it is with water. As a matter of fact, it is contemplated that a closed coiled pipe shaped similar to that of the heating unit 40 in Figure 2 would better serve, in using hot water for heating the calender rolls, than would the arrangement shown in Figure 6. Of course, inlet and outlet hot water conduits would then be connected to opposite ends of the closed coiled pipe.

In the drawings and specification there has been set forth a preferred embodiment of the invention and, although specific terms are employed, they are used in a generic and descriptive sense only and not for purposes of limitation, the scope of the invention being defined in the claims.

I claim:

1. That method of treating a fibrous web on a lap forming machine, provided with a set of calender rolls through which the web passes, which includes directly spraying moisture on said web of fibers after formation of said web and in advance of passage thereof through the calender rolls and applying heat at a temperature substantially above normal room temperature to the fibrous web in its course through the calender rolls to thereby cause the fibers to tend to adhere to each other and to thereby remain compacted as they are discharged from the calender rolls.

2. In a lap forming machine having-lap forming condensing screens, a set of calender rolls in spaced subsequent flow relation from said condensing screens, and means for forming a lap roll from lap passing from'said condensing screens and through said calender rolls; the combination therewith of spray means for spraying moisture onto said lap subsequent to passage of said lap from said condensing screens, said spray means being disposed in subsequent flow relation to said condensing screens, and means for heating said lap as it passes through said calender rolls.

3. A structure according to claim 2 wherein said means for heating the lap includes at least one electrical heating unit disposed closely adjacent the path of travel of the lap and closely adjacent at least one of said rolls and said heating unit being so arranged as to radiate heat to the lap.

4. A structure according to claim 3 wherein the heating unit is of the infrared type.

5. In a picker machine having means for forming a lap from textile fibers, a set of calender rolls disposed in subsequent flow relation to said means for forming a lap, and means for withdrawing the lap from the calender rolls and forming a lap roll from said lap; the combination of liquid spraying means for spraying liquid onto said lap subsequent to formation of said lap and passage of said lap from said lap forming means and prior to the passage of said lap through said rolls, said spraying means being disposed in subsequent flow relation to said lap forming means, and heating means for heating one of said calender rolls to thereby heat said lap as it passes through said set of calender rolls.

6. A structure according to claim 5 wherein the means for heating said one of the rolls includes the latter roll being of hollow construction, means co-axial with said latter roll for introducing steam into the latter roll, and means for withdrawing condensate from the latter roll, said condensate withdrawing means including a condensate withdrawing conduit extending within said latter roll and connecting between the lower portion of the interior of said latter roll and the exterior of said latter roll, a portion of said condensate withdrawing conduit passing through the interior of said introducing means in the course of its passage from the interior of said roll to the exterior thereof.

7. A structure according to claim wherein said one of the calender rolls is of hollow construction, said means for heating the latter calender roll comprising an electrical heating unit disposed within the latter calender roll, and thermostatic control means interposed in an electrical circuit to said electrical heating unit whereby the heating unit maintains the corresponding roll at uniform temperature during passage of the lap in engagement therewith.

8. A structure according to claim 5 wherein said one of the calender rolls is of hollow construction, said means for heating the latter calender roll comprising an electrical heating unit disposed within the latter calender roll and interposed in an electrical circuit to said electrical heating unit whereby the heating unit maintains the corresponding roll heated during passage of the lap in engagement therewith.

9. A structure according to claim 5 wherein said one of the rolls is of hollow construction, and said means for heating the latter roll includes means for circulating hot water through the latter roll, said circulating means including a water inlet conduit co-axial with the axis of said latter roll, and a separate water outlet conduit substantially coaxial with said inlet conduit at the point of entry onto said latter roll.

10. The method of treating afibrous web on a lap forming machine provided with a set of calender rolls through which the web passes, which includes substantially penetrating the major thickness of said web with moisture after formation of said web and in advance of final passage thereof through the calender rolls and applying heat at a temperature substantially above normal room temperature to the fibrous web in its course through the calender rolls to thereby cause the fibers to tend to remain compacted as they are discharged from the calender rolls.

11. In a picker machine having means for forming a lap from textile fibers, a set of calender rolls disposed in subsequent flow relation to said means for forming a lap, and means for withdrawing the lap from the calender rolls and forming a lap roll from said lap; the combinationof lap-penetrating moisture-applying means for applying moisture in web-penetrating form and manner to said lap subsequent to formation of said lap and passage of said lap from said lap forming means and prior to final passage of said lap through said rolls, said moisturepenetrating means being disposed in subsequent flow relation to said lap forming means, and heating means for heating one of said calender rolls to thereby heat said lap as it passes through said set of calender rolls.

References Cited in the file of this patent UNITED STATES PATENTS 21,988 Smith Nov. 2, 1858 1,442,793 Brown Jan. 23, 1923 2,043,586 Kronheim June 9, 1936 2,068,139 Kronheim Jan. 19, 1937 2,206,297 Curley et al. July 2, 1940 2,446,840 Leister Aug. 10, 1948 2,647,286 Hotfman Aug. 4, 1953 FOREIGN PATENTS 3,002 Great Britain of 1862 8,939 Great Britain of 1886 

